This paper produces a modern meta-heuristic optimization technique based on the buoyancy principle called the Archimedes optimization algorithm (AOA). The proposed algorithm is used here to determine the optimal economic operation of interconnected micro-grids (IMGs). Each micro-grids (MG) includes different types of distributed generation (DG) units such as solar photovoltaic (PV), wind turbine (WT), and micro-turbine (MT) and aims for achieving minimization of total power generation cost as the main objective function taking into consideration the power exchange between the IMGs and utility with special emphasis on technical constraints. To prove the effectiveness of the proposed AOA algorithm, it is compared with another optimization method based on the particle swarm optimization algorithm (PSO). Results obtained with the AOA algorithm show how managing energy transfer between utility and each MG. For various daily loads, it can reduce electricity consumption while lowering the cost of overall electricity generation, minimizing utility bills, and maximizing micro turbine (MT) efficiency.